1. Field of the Invention
The present invention concerns a method for determination of imaging parameters for the acquisition of an image of an examination subject with the use of an image acquisition device. The invention can be used in particular (but not exclusively) in the planning of examinations in a magnetic resonance (MR) system in which imaging parameters must be set for the acquisition of the individual MR images.
2. Description of the Prior Art
With increasing complexity of MR imaging methods, it is increasingly difficult and time-consuming for the operator to generate protocols with imaging sequences in which the set imaging parameters deliver the desired contrast and the required image quality. Variants of a three-dimensional acquisition method with the use of the gradient echo technique—such as, for example, turbo-flash imaging (MPRAGE—magnetization prepared rapidly acquired gradient echoes)—are examples. The setting of the imaging parameters is particularly difficult when optimized, central k-space scanning methods, variable flip angles and/or different preparation pulses are used in such imaging sequences. As a result, the image quality of the measured MR image may become clinically unusable given a change of an imaging parameter (such as, for example, the change of an excitation flip angle by 1°).
Protocol development, i.e. the determination of suitable imaging parameters for specific imaging sequences, essentially ensues with the use of a testing strategy in which, starting from an existing protocol that delivers an average image quality, the imaging parameters are iteratively optimized by measurements (data acquisitions) using measurement phantoms or using volunteer test subjects. This process is very time-consuming and cost-intensive, particularly in the case of imaging sequences with very long acquisition times. This is particularly true in the field of pediatric imaging, since there the MR-relevant tissue parameters differ distinctly form those for adults; dedicated imaging parameters must thus be determined, but test subject measurements naturally can be made only in a very limited manner in pediatrics.